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    <script>
        let a = [1, 23, 23, 23, "12321", "12789", "asdas", "bnvbn"]
        // let a1 = a.splice(4, 2)
        let b = a.join(" ")
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        let a1 = a.splice(4, 2, "qwerty")
        console.log(a)
        console.log(a1)
        let a2 = a1.reverse()
        console.log(a2)
        console.log(a1)
        let a3 = a2.concat(a1)
        console.log(a3)

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